Uzwil, May 11, 2010 – The Buhler Group is making selected dispersions of inorganic nanoparticles accessible worldwide to materials science researchers through an exclusive distribution agree-ment with Sigma-Aldrich.

Buhler and Sigma-Aldrich® (Nasdaq: SIAL) have signed an agreement in which research volumes of nanoparticle dispersions from Buhler will be sold worldwide exclusively by Sigma-Aldrich. These prod-ucts are dispersions of nanoscale inorganic particles in water and organic solvents, which show great economic potential in a wide spectrum of possible applications. The initial target group for these prod-ucts will be materials science research and development. The dispersions are manufactured in the nanotechnology business unit (PARTEC) of the Buhler Group and are sold worldwide through the Al-drich® Materials Science initiative of Sigma-Aldrich.

The agreement covers dispersions of nanoscale titanium dioxide (TiO2), zinc oxide (ZnO) and hydrated iron oxide (FeOOH). Dispersions of nanoscale titanium dioxide in water, xylene and a mixture of ethyl-ene glycol open up development options for the photocatalytically active semiconductor material in such diverse fields as solar energy, printed electronics, and self-cleaning and superhydrophilic surfaces. Dispersions of hydrated iron oxide are available in water and ethanol. Dispersions in water, ethanol, butyl acetate and butyl glycol provide a wide solvent polarity spectrum for researching applications of the nanoscale zinc oxide. Zinc Oxide is already being used in UV absorbers and as a fungicide in coat-ings, and as a ceramic for electronic components such as varistors. To learn more about the nanomate-rials available from Aldrich Materials Science, please visit www.sigma-aldrich.com/nano.

Buhler is a global leader in the supply of process engineering solutions, especially production technologies for producing foods and engineering materials. Buhler operates in over 140 countries and has a global payroll of about 7,500. In fiscal 2009, the Group generated sales (turnover) of CHF 1.7 billion.

Sigma-Aldrich is a leading Life Science and High Technology company. Its biochemical and organic chemical products and kits are used in scientific and genomic research, biotechnology, pharmaceutical development, the diagnosis of disease and as key components in pharmaceutical and other high tech-nology manufacturing. The Company has customers in life science companies, university and govern-ment institutions, hospitals, and in industry. Over one million scientists and technologists use its prod-ucts. Sigma-Aldrich operates in 38 countries and has 7,600 employees providing excellent service worldwide. Sigma-Aldrich is committed to Accelerating Customer Success through Innovation and Leadership in Life Science, High Technology and Service. For more information about Sigma-Aldrich, please visit its award-winning Web site at http://www.sigma-aldrich.com.

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